Power-shovel.



E. J. ARMSTRONG.

POWER SHOVEL.

APPLICATION FlLED JULY 23,19I4.

Patented Dec. 14, 1915.

2 SHEETS-SHEET I.

E. J. ARMSTRONG.

POWER SHOVEL.

APPLICATION FILED JULY 23, 1914.

Patented Dec. 14, 1915.

2 SHEETSSHEET Z.

lllllllllll liljlllll aim y LS: 1 Eww W I TD STATES PA EN F EDWIN J. ARMSTRONG, 0P ERIE, PENNSYLVANIA, AssIca-ioa TO BALL ENGINE COMPANY, or ERIE, PENNSYLVANIA, A conPoaArIoN or PENNSYLVANIA.

POWER-SHOVEL.

Specification of Letters Patent.

Patented Dec. 14, 1915.

To all whom it may concern:

Be it known that I, EDWIN J. ARMSTRONG, a citizen of the United States, residing at Erie, in the county of Erie and State'of Pennsylvania, have invented new and useful Improvements in Power- Shovels, of which the following is a specification.

This invention relates to power shovels and consists in certain improvements in the construction thereof as will be hereinafter fully described and pointed out in the claims.

More particularly the invention relates to improvements in power shovels whereby the cutting lip of the dipper may be made to travel in a pre-determined line so as to finish the grade at the completion of the excavation either as a plane surface or a grade having some pitch as for an ordinary road-way.

The invention is illustrated in the accom panying drawings as follows: 1

Figure 1 hows a side elevation of the machine. 7 Fig. 2 a section on the line 22 in Figs. 1 and 3. Fig. 3 an enlarged View of the dipper stick and actuating mechanism.

1 marks the carriage, 2 the .turn table and 3 the boom. The boom is supported by the usual stay 4 extending to the base 5 and the stays -6 returning to the-turn table 2; These are of ordinary construction, 7 I The dipper 7 is carried by the dipper stick 8. Ithas a cutting lip 9. The dipper stick is provided with the racks 10 engaging the ears 11. The gears 11 are carried by a shaft 12. The shaft 12 is mounted in boxes 12 carried by the boom 3. A yoke 13 is pivotally mounted on the shaft 12 and forms .a

sliding-connection in which thedipper stick is mounted, the dipper stick swingmg pivotally with the shaft 12 as acenter, the yoke swinging with it and the stick sliding in the yoke as the gears 11 operate the racks .10. The shaft 12 is driven-by a gear 14, the gear 14 meshing a gear 15. The gear 15 is driven directly by the engine 16. The engine is provided with the ordinary controlling mechanism 17 whereby the gear 15 may be.

rotated in either direction or stopped at any point.v A link 18 leads from'the controlling mechanism 17 to an adjusting lever 18. The adjusting lever is carried by a hand lever 19 and swings with it so that by operating thehand lever, the controllin lever orv mechamsm17 may be actuate tionI A pulley block 20 is secured to the dipper and a cable 21 runs from this block over a block 22 back to the hoisting engine 23 on the turn table. The dipper is swung or given pivotal movement by the action of the cable 21 and is operated in the sliding connectlon or givensliding movement by the action of the gears 11 on the racks 10.

It will be observed that while an operator could within limitsby manual operation of the control 17 so control the sliding movement of the dipper stick 8 as to make the cutting lip 9 follow some desired path it Wlll be understood that this movement ofthe dipper stick must be synchronous with the swmging movement under the in'fiuence of the cable 21 and must vary in extent with I different portions of the travel of the dipper.

If no sliding movement were given to the lifting of the dipper prior to thelfull sweep of the stick. lprovide a mechanism which ,Will automatically actuate the controlling mechanism to control the engine'lti so as to 'make the dipper stick follow a pre-determined line provided pressure is exerted on the operating lever so as to follow this automaticmechanism. A rack 24 is mounted in a guide 25, the guide 25 being carried by the yoke 13 so that, the guide 25' swings with the dipper stick "8. The rack 24 meshes with a gear 26 on the shaft 12. Thi gear 26 is.

preferably smaller than the gear 11 so that while thetravel of the rack'24 is propors tiqnal at all times'to the travel of the dipper stick yet it is very much less. The end of the rack engages a cam lever 27. This cam lever is pivoted at 27 on the engine frame' A link 28 connects the cam lever 27 with the adjusting lever 18*; It will be readily seen that if the hand lever 19 is forced forward the cam lever 27 will be forced forward into contact with the'end of the rack 24 and that if pressure is exerted on the hand lever 19,

the cam lever 27 will be kept in contactwith the end of the rack 24. The surface of the cam lever is so formed withrelation to the 2 1,1es,eee

travel ofthe rack 24 that the controlling mechanism 17 will be brought to neutral only with a position of the cutting lip 9 somewhere in the pro-determined line A. It

will be understood that the controlling mechanism 17 when at neutral will bringthe engine to a stop but that with the controlling mechanism in either direction from neutral the engine will be driven in one or theother direction, in one direction lifting the dipper and in .the reverse direction lowering the dipper. This is a common construction of these mechanisms. To more readily understand the operation of the automatic control let us assume that the point of the dipper is above the line A. The small rack 2-1: will then be toward the right of the neutral position, thus allowing the cam lever 27 if it is held in Contact with the end of the rack 24 to be to the right. The controlling lever 19 which is ordinarily grasped by the operator will also be to the right and the controlling mechanism 17 will be to the right. The controlling mechanism 17 ordi narily is such that with a forward movement (toward the right) of the lever19, the dipper is depressed. Consequently with the cam lever 27 toward the right of the neutral position and the lever 19 toward the right of theneut-ral position of the engine steam will be on the engine and the engine will be traveling to lower the dipper stick, As the dipper is lowered so asto approach the line A, the gear 26 is rotated thus moving the rack A toward the left and as the rack 24 is moved toward the left, it forces the cam lever 27 toward the left and this in turn through the links and levers forces the controllingmechanism toward the neutral position and this will continue until the controlling mechanism 17 reaches the neutral position when the engine will come to a stop. The cam lever is so shaped that this position will be reached with the point 9 at the line A and this neutral position will be reached with the point 9 at the line A regardless of where the dipper is along the line A. T his will be just as true with the dipper in the position shown in dotted lines in Fig. 1 as in the position shown in solid lines. On the other hand if the point of the dipper should be below the line A this would have forced the cam lever to the left of the neutral position and this would have put the engine in motion to lift the dipper stick. If, however, the operator exerts pressure on thelever 19 so that the cam lever 27 follows the rack 24 in its movement toward the right. the controlling mechanism 17 will be moved toward neutral position with this upward movement of the dipper and will reach the neutral position when the dipper reaches the line A. It will be understood that in the normal operation of the machine, however, there is no distinct succession of movements.

ing links on the controlling mechanism. If

the operator then exerts pressure on the lever 19, the engine will go faster or slower depending on how great a departure from the neutral position the levers are and in this way the engine will maintain the point 9 approximately along the line A. The engine cannot be at rest with the dipper away from this point because the controlling mechanism is forced. away from neutral by'a posi tion of the dipper stick away from this line. This automatic control ofthe line of travel of the dipper not only accomplishes the finishing of the grade by the action of the dipper but also adds very much to the speed at which the shovel may be operated where excavation alone is desired because the operator in lowering the dipper to work can lower it at full speed and depend on the automatically controlled mechanism to re-- tard and stop the dipper when properly lowered. This retarding and stopping of the dipper is accomplished without shock or jar because it is done by the engine itself, the steam forming a cushion for stopping the movement. This is true because if the dipper tends to go beyond the line determined ;tor the lower line, as A, the engine is reversed and the dipper moves directly against the driving power of the engine so that if there is any tendency to over-run the engine catches-it and returns the dipper to the pro-determined position. In the normal operation, however, there is no material over-running because as soon as the dipper stick has dropped far enough to bring the cutting lip 9 to this pie-determined line a rearward action of the rack 24 will have forced the lever 27 toward the rear sulfioiently to bring the controlling mechanism 17 to neutral. At all times, however, the hand lever 19 may be pulled back or toward the left as shown in Fig. 1 so as to lift the dipper stick as dsired.

T prefer to provide the adjusting lever 18 This has a latch 30 which engages the catches 31 on a quadrant 32 extending from the hand lever 19. By changing the adjustment of the lever 18 the position of the cam lever 27 which will bring the controlling a boom; a dipper having a cutting lip; a

dipper stick on which the dipper ismounted having'a pivotal and sliding connection with the boom mechanism for swinging the dipper on the pivotal connection; a rotating device imparting a sliding movement to' the stick 'on the sliding connection synchronously with the pivotal movement; a motor for actuating said device; and means controlling the motor and actuated by the device for limiting the movement of the lip of the dipper toa predetermined line involving a synchronous swinging and sliding movement of the dipper stick.

2. In a power shovel, the combination of .a boom; a dipper having a cutting lip; a

dipper stick on which the dipper is mounted having a pivotal and sliding connection with the boom; mechanism for swinging the dipper on the pivotal connection; a rotating device imparting asliding movement to the stick on the sliding connection synchro-,

nously with the pivotal movement; a motor for actuating said device; and means controlling the motor and actuated by the device for limiting the movement of the lip of the dipper to a predetermined line involving a synchronous swinging and sliding movemerit-of the dipper stick, said means being treeior manual operation to move the dipper stick in one direction to control the dipper stick at points above said line.

3. In a power shovel, the combination of a boom; a dipper having'a cutting lip; a

- dipper stidk on which the dipper is mounted having a pivotal and sliding connection With the boom; mechanism for swinging the dipper/on the pivotal connection; a rotating device iinparting a sliding movement to the stick and the sliding connection synchronously with the pivotal movement; a motor for actuating said device; means controlling the motor; and actuated/by the device .for limiting the movement of the lip of the dipper to a predetermined line involving a synchronous swinging and sliding movement-of the dipper stick; and apparatus for varying and controlling the means to vary theline through which the dipper lip moves.

4. In a power shovel, the combination of a boom; a dipper having a cutting lip; a

dipper stick on which the dipper is.mounted having a pivotal and sliding connection with the boom: mechanism for swinging the'dipper on the pivotal. connection; a rack on the dipper stick: a driving gear meshing with .the rack: a shaft on which thedriving gear is mounted. the axis of the shaft being the axis of the pivotal connection of the stick with the boom: a motor for actuating said driving'ge'ar; a' eoutroll'ing means for the dipperstick' on which the dipper is mounted I having a pivotal and sliding connection with the boom; mechanism for swinging the dipper on the pivotal connection; a rack on the dipper stick; a driving gear meshing with the rack; a shaft on which the driving gear is mounted; the axis of the shaft being the axis of the pivotal connection of the stick with the boom; a motor for actuating said driving gear; a controlling means for the motor; a controlling gear on the shaft; a controlling rack slidingly mounted to swing with the stick and meshing the controlling gear; and devices actuated by the controlling rack and acting on said means to control the motor to limit the movement of the lip of the dipper to a predetermined line involving a synchronous pivotal and sliding movement of the stick, said means being free for manual, operation to move the dipper stick in one direction to control the dipper stick at points above said line.

6. In a power shovel, the combination of a boom; a dipper having a cutting lip; a dipper stick on which the dipper is mounted having a pivotal and sliding connectioncontrol the motor to limit the movement of the lip of the dipper to a predetermined line involving a synchronous pivotal and sliding movement of the stick; and apparatus for varying and controlling the means to vary the'line through which the dipper lip moves. r v a 7. In a power shovel, the combination of a boom; a dipper having a cutting lip; a dipper stick on which the dipper is mounte'd having ajpivotal and sliding connection with the boom; mechanism for swinging the dipper on the pivotal connection; a rack on the dipper st1'ck;. a driving gear meshing with the rack a shaft on which the driving v with the stick with the boom; mechanism for swinging a the dipper stick;

' trolling gear;

line invglvlng'a synchronous pivotal gear is mounted, the aXis of the shaft being the axis of the pivotal connection of the stick with the boom; a motor for actuating said driving gear; a controlling means for the motor; a controlling gear on the shaft; a controlling rack slidingly mounted to swing and meshing the controlling gear; and devices actuated by the controlling rack and acting on said means to control the motor to limit the movement of the lip of the dipper to a predetermined line involving a synchronous pivotal and sliding movement of the stick, said devices comprising a cam lever on which the controlling rack operates; a hand lever connected with the cam lever; and a connection between the hand lever and said means.

8. In a power shovel, the combination of a boom; a dipper having a cutting lip; a dipper stick on which the dipper is mounted ed having a pivotal and sliding connection the dipper on the pivotal connection; a rack on a driving gear meshing with the rack; a shaft on which the driving gear is mounted, the axis of the shaft being the aXis of the pivotal connection of the stick with the boom; a motor for actuating said driving gear; a controlling means for the motor; a controlling gear on the shaft; a controlling rack slidingly mounted to swing with the stick and meshing the..con-

and devices actuated by the controlling rack and acting on said means to control the motor to limit the movement of the lip of the dipper to a predetermined and sliding movement of the stick, said devices comprising a cam lever on which the controlling rack operates; a hand lever con;

nected with the cam lever; and a connec- Copies of this patent may be obtained tion betwcen the hand lever and said means,

said hand lever being free for manual operation to move the dipper stick in one direction to control the dipper stick at points above said line.

9. In a power shovel, the combination of a controlling rack slidingly mounted to swing with the stick and meshing the controlling gear; devices actuated by the controlling rack and acting on said means to control the motor to limit-the movement of the lip of the dipper to a predetermined line involving a synchronous pivotal and sliding movement of the stick, said devices coinprising a cam lever on which the controlling rack operates; a hand lever connected with the cam lever; a connection between the hand lever and said means, and means for adjusting one of said connections to vary the predetermined line to which the travel of the lip of the dipper is limited. y

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

EDWIN J. ARMSTRONG.

WVitnesses:

a B. M. HARTMAN,

THOMAS C. MILLER-- for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

